A position-measuring system of this type is known, for example, from European Patent EP 0 470 291 B1. This position-measuring system is used for determining the position of a first object relative to a second object which is movable relative thereto along at least one measurement direction. This system is provided, on the one hand, with a scale connected to the first object and extending along the first measurement direction. The scale includes a measuring graduation composed of graduation regions which are alternately arranged along the measuring direction and have different optical properties. On the other hand, a scanning unit including at least one light source, a detector array and a fiber-optic array is connected to the second object. The fiber-optic array is composed of a plurality of optical fibers arranged adjacent one another, whose image-input faces face the scale and whose image-output faces face the detector array. As a result of the interaction of the beams emitted by the light source with the measuring graduation, a light pattern is produced which is transmitted by the fiber-optic array into a detection plane of the detector array. Using the detector array, position-dependent signals regarding the position of the two relatively movable objects can be generated from the detected light pattern and transmitted to subsequent electronics.
A position-measuring device of this kind makes it possible in a machine, for example, to determine the position of a movable machine component relative to a machine frame which is stationary with respect thereto. Thus, the movable machine component on the one hand, and the stationary machine frame on the other hand, act as the two relatively movable objects here. The subsequent electronics used is a higher-level machine controller, which uses the generated position-dependent signals for positioning the movable machine component, for example.